Radio apparatus capable of detecting its position and position search method

ABSTRACT

When receiving an incoming call, a portable telephone that receives a search request judges whether or not this incoming call is the search request sent from a second portable telephone, which is a source of the search request. When the portable telephone judges that the incoming call is the search request sent from the second portable telephone, it is judged whether or not the receiving portable telephone is capable of determining its position information. When the portable telephone is incapable of determining its position information, the portable telephone automatically switches to a response hold state and transmits a search response message to the second portable telephone based on information stored in advance. Further, when the portable telephone is capable of determining its position information, the portable telephone determines its position information and transmits the position information to the portable telephone.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a radio apparatus that detectsthe position of the radio apparatus and transmits the positioninformation to a search requester. The present invention also relates toa position search system and a position search method using such anapparatus.

[0003] 2. Description of the Related Art

[0004] In recent years, various systems have been developed that use aportable telephone capable of determining its own position information.For example, there is a position search system in which, when a portabletelephone receives a search request from a third party, the portabletelephone determines its position information and transmits the positioninformation to the third party.

[0005]FIG. 1 is a flowchart showing the operation of such a portabletelephone. In FIG. 1, when the portable telephone (which is thedestination of the search request) gets an incoming call (S11), theportable telephone performs an incoming call response regardless of thecontent of the incoming call (S12). Next, the portable telephonedetermines whether or not the source of the incoming call will receivethe results of the search request sent from the third party, e.g.,another portable telephone which is the source of the search request(S13). When the portable telephone determines that the source of theincoming call will not receive the results of the search request, theportable telephone performs a normal incoming call processing (S14). Onthe other hand, if the portable telephone determines that the incomingcall will be receiving the results of the search request, thepositioning mechanism provided in the portable telephone judges whetherthe portable telephone is capable of determining its positioninformation (S15). When the positioning mechanism judges that theportable telephone is incapable of determining its position information,the portable telephone completes the operation without transmitting anyposition information to the portable telephone that is the source of thesearch request (S16). On the other hand, when the positioning mechanismjudges that the portable telephone is capable of determining itsposition information, the portable telephone checks received informationregarding the portable telephone that is the source of the searchrequest (S17) and performs determines its position information (S18).The position information is then transmitted to the portable telephonethat is the source of the search request (S19).

[0006] However, in the above-described position detecting system, whenthe portable telephone receives a search request from a third party whenit is incapable of determining its position information, the portabletelephone cannot transmit the position information to the third partybecause the portable telephone cannot determine its positioninformation. Therefore, when the third party does not get a response tothe search request, the third party is unaware of the reason, e.g., theportable telephone did not receive the search request sent by the thirdparty, the portable telephone is incapable of determining its positioninformation, the portable telephone rejected the incoming call of thesearch request, or the portable telephone rejects determining itsposition information.

SUMMARY OF THE INVENTION

[0007] Accordingly, an aspect of the present invention is to provide aradio apparatus capable of informing the search requester of the reasonfor not responding to the search request even when the radio apparatusreceives the search request from the search requester in the situationwhere the radio apparatus is incapable of determining its positioninformation.

[0008] To achieve the above aspect, a radio apparatus of the presentinvention comprises a receiving means for receiving a radio signal, ajudging means for judging whether the radio apparatus is capable ofdetermining its position information and a setting means for setting aresponse hold state when the radio apparatus is incapable of determiningits position information. The radio apparatus further comprises asending means that sends a message to a sender of the radio signal. Theradio apparatus may further comprise a checking means that checks if theradio signal includes the information showing a search request forposition information. Preferably, the radio apparatus comprises astoring means that stores in advance a message for each search requestsender. In addition, the setting means sets a response hold state andthe sending means sends the message even if the radio apparatus iscapable of determining its position information. The radio apparatusfurther comprises a positioning means for determining its positioninformation and a sending means that send the result of the positioningmeans to a sender of the radio signal. Preferably, the message showsthat the radio apparatus is incapable of determining its positioninformation. The message may show that the radio apparatus rejectsdetermining its position information. The message may be the latestpositioning data of a plurality of positioning data. Moreover, themessage may be the position information of a base station locatednearest to the radio apparatus. Prefereably, the radio apparatus is aportable telephone.

[0009] Another aspect of the invention provides a position search systemthat comprises a first radio apparatus and a second apparatus. The firstradio apparatus comprises a receiving means that receives a radio signalfrom the second radio apparatus, a judging means that judges whether thefirst radio apparatus is capable of determining its position informationand setting means that sets a response hold state when the first radioapparatus is incapable of determining its position information. Thefirst radio apparatus further comprises a sending means that sends amessage to the second radio apparatus. The first radio apparatus mayfurther comprise a checking means that checks whether the radio signalincludes the information showing a search request of positioninformation. The first radio apparatus further comprises a storing meansfor storing the message previously determined on the basis of the secondradio apparatus. The first radio apparatus sets a response hold stateand sends the message to the second radio apparatus even if the firstradio apparatus is capable of determining its position information. Thefirst radio apparatus further comprises a positioning means thatdetermines is position information and a sending means that sends theresult of the positioning means to the second radio apparatus. The sentmessage may show that the first radio apparatus is incapable ofdetermining its position information. The sent message may also showthat the first radio apparatus rejects determining its positioninformation. The content of the message is preferably the latestpositioning data from a plurality of positioning data. The sent messagemay also be the position information of a base station located nearestto the first radio apparatus. At least one of the first radio apparatusand the second radio apparatus is a portable telephone, and both can beportable telephones.

[0010] Another aspect of the present invention provides a positionsearch method for searching a position of a radio apparatus. The methodcomprises receiving a radio signal, judging whether the radio apparatusis capable of determining its position information and moving to aresponse hold state when the radio apparatus is incapable of determiningits position information. The position search method further comprisessending a message to a sender of the radio signal. The position searchmethod may comprise checking whether the radio signal includes theinformation showing a search request of position information.Preferably, the position search method comprises storing the message foreach of the senders. The position search method may further comprisemoving to a response hold state when the radio apparatus is capable ofdetermining its position information and sending a message to a senderof the radio signal. Moreover, the position search method comprisesdetermining the position information of the radio apparatus and sendingthe positioning result to a sender of the radio signal. The radioapparatus is preferably a portable telephone.

[0011] In the present invention, when the radio apparatus which receivesa search request from the third party in the situation where the radioapparatus is incapable of determining its position information, theradio apparatus automatically switches to a response hold state andtransmits information showing that the radio apparatus is unable todetermine its position information, or a similar message, to the searchrequester as a search response message. Therefore, the search requesteris consistently able to obtain some information even when the radioapparatus that is the destination of the search request is unable todetermine its position information.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] These and other aspects, features and advantages of the inventionwill become more fully apparent from the following detailed descriptiontaken in conjunction with accompanying drawings:

[0013]FIG. 1 is a flowchart showing an operation of a portable telephonerelated to the present invention;

[0014]FIG. 2 shows an exemplary embodiment of a position detectingsystem of the present invention;

[0015]FIG. 3 is a block diagram showing an exemplary construction of theportable telephone 15 in FIG. 2; and

[0016]FIG. 4 is a flowchart showing an operation of a portable telephoneof the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an exemplary embodiment of the present inventionwill be described in detail with reference to the drawings.

[0018]FIG. 2 shows an exemplary embodiment of a position detectingsystem of the present invention. As shown in FIG. 2, the presentinvention is comprised of a radio apparatus, preferably a portabletelephone 11 which is a first portable telephone, a portable telephone15 which is a second portable telephone, a base station 12, a portabletelephone network 13 and a base station 14. The portable telephone 11 isa source of a search request and transmits a search request to theportable telephone 15 in order to obtain the position information of theportable telephone 15. This search request is sent out into the portabletelephone network 13 via the base station 12 and arrives at the portabletelephone 15 via the base station 14 located near the portable telephone15. When the portable telephone 15 (the destination of the searchrequest) is capable of determining its position information and receivesthe search request sent from the portable telephone 11 (the source ofthe search request), the portable telephone 15 transmits a search resultcorresponding to the search request to the portable telephone 11. Thesearch result is sent out into the portable telephone network 13 via thebase station 14 and arrives at the portable telephone 11 via the basestation 12 located near the portable telephone 11.

[0019]FIG. 3 is a block diagram showing an exemplary construction of theportable telephone 15 that receives the search request shown in FIG. 2.As shown in FIG. 3, the portable telephone 15 comprises a wirelesscontrol unit 21 for receiving the search request and a RAM 23, which isa memory area for storing in advance an identification of the portabletelephone 11 used by the search requester or the information sent fromthe portable telephone 11 that corresponds to the search request. Theportable telephone 15 further comprises a ROM 24 that is a program areafor recording a control program, and an operating unit 25 for operatingthe portable telephone 15. The portable telephone 15 further comprises apositioning mechanism 26 for determining the position information of theportable telephone 15, and a control unit 22 for controlling thewireless control unit 21, the RAM 23, the ROM 24, the operating unit 25and the positioning mechanism 26.

[0020] In the present invention, a plurality of portable telephones,each of which is a potential source of a search request, may beconfigured. When a plurality of portable telephones are used, the RAM 23of the portable telephone receiving the search request storesinformation such as identification numbers of the requesting portabletelephones or the information sent from the receiving portable telephonethat corresponds to the search request from each of the requestingportable telephones, i.e., the sources of the search requests.

[0021] The operations of the portable telephone 15, which receives thesearch request in the position detecting system shown in FIG. 2 andconfigured as described above, will be described below with reference toFIG. 4. In FIG. 4, when the wireless control unit 21 receives anincoming call (S41), the portable telephone 15 judges whether theincoming call is a search request sent from the portable telephone 11 ornot (S42). When the portable telephone 15 judges that this incoming callis a search request sent from the portable telephone 11, the portabletelephone 15 performs the normal incoming call processing (S43). On theother hand, when the portable telephone 15 judges that the incoming callis a search request sent from the portable telephone 11, the positioningmechanism 26 judges whether the portable telephone is in the situationcapable of determining its position information or not (S44). When thepositioning mechanism 26 judges that the portable telephone 15 iscapable of determining its position information, the normal processingfor receiving the search request is performed (S45), such as thepositioning mechanism 26 determining the position information and thetransmission of the position information to the requesting portabletelephone 11. On the other hand, when the positioning mechanism 26judges that the portable telephone 15 is incapable of determining itsposition information, the portable telephone 15 automatically switchesto a response hold state without sending the incoming call response(S46). Next, the portable telephone 15 checks the identificationinformation of the requesting portable telephone 11 (S47). Theinformation for responding, stored in advance in the RAM 23, is read outbased on the identification of the requesting portable telephone (S48).The portable telephone 15 transmits the search response message to theportable telephone 11 based on the response information being read outfrom the RAM 23 (S49).

[0022] For example, the search response messages transmitted to theportable telephone 11 may state “incapable of determining positioninformation” or “rejecting the search request”. When the positioningdata is periodically stored in the RAM 23 or another storage device, thelatest positioning data at the time of receipt the search request may besent as the search response message. Alternatively, in order to indicatethe approximate position of the portable telephone 15, the positioninformation of the closest base station at the time of receipt thesearch request may be sent as the search response message.

[0023] In the exemplary embodiment, the portable telephone 15automatically switches to the response hold state and sends the searchresponse message while the portable telephone 15 is incapabledetermining its position information. However, even when the portabletelephone 15 is capable of determining its position information, theportable telephone 15 may automatically switch to the response holdstate and send the search response message, depending on the informationpreviously stored in RAM 23 corresponding to each of the portabletelephones that sent a search request. In this case, after the portabletelephone 15 receives the search request sent from the requestingportable telephone and confirms that the portable telephone 15 iscapable of determining its position information, the portable telephone15 reads out the response information previously stored in the RAM 23and sends the information to the requesting portable telephone. Thus,even in the situation where the portable telephone is capable ofdetermining its position information, the portable telephone canautomatically switch to the response hold state, depending on theresponse information stored for each of the portable telephones thatsend search requests. The search response messages sent when theportable telephone is capable of determining its position informationare preferably the same as those messages sent when the portabletelephone is incapable of determining its position information.

[0024] In the exemplary embodiment, the portable telephone, whichreceives the search request, automatically switches to the response holdstate without sending the incoming call response to the search request.However, the portable telephone, which receives the search request, mayperform the incoming call response to the search request and thereafterautomatically switches to the response hold state. Users can selectwhether the portable telephone switches to the response hold statewithout sending the incoming call response to the search request or theportable telephone switches to the response hold state after sending theincoming call response to the search request.

[0025] Since the present invention is constructed as described above,the present invention can obtain effects as described below.

[0026] In the case where the portable telephone receives the searchrequest from the search requester and the portable telephone isincapable of determining its position information, the portabletelephone automatically switches to the response hold state andtransmits the search response message to the search requester.Therefore, even when the portable telephone is incapable of determiningits position information, the search requester can consistently obtainsome information. This avoids the inconvenience of not obtaining anyresponse to the search request or having to wait for several hours dueto no response to the search request.

[0027] The portable telephone which receives the search requestpreviously stores response information corresponding to the searchrequest from each of the search requesters. Therefore, the portabletelephone can send different information or different response messagesto each of the portable telephones that send a search request.

[0028] When a portable telephone receives the search request and theposition information of the closest base station at the time of receiptthe search request is sent as the search response message, the searchrequester can obtain the information of the area where the portabletelephone receiving the search request is located, even when thereceiving portable telephone cannot determine its position information.

[0029] Since the latest positioning data is accumulated and stored, andthereafter is sent as the search response message, the search requestercan obtain the information of the approximate position of the receivingportable telephone even when the receiving portable telephone cannotdetermine its position information.

[0030] In the portable telephone that receives a search request, userscan select whether the portable telephone switches to the response holdstate without sending the incoming call response to the search requestor the portable telephone switches to the response hold state aftersending the incoming call response to the search request. Therefore, theusers of the portable telephone that receives the search request avoidthe inconvenience of always performing the incoming call response.

[0031] Obviously, numerous additional modifications and variations ofthe present invention are possible in light of the above teachings. Itis, therefore, to be understood that within the scope of the appendedclaims, the invention may be practiced otherwise than as specificallydescribed herein.

What is claimed is:
 1. A radio apparatus comprising: receiving means forreceiving a radio signal; judging means for judging whether saidapparatus is capable of determining its position information; andsetting means for setting a response hold state when said apparatus isincapable of determining its position information.
 2. The radioapparatus as claimed in claim 1, further comprising sending means forsending a message to a sender of said radio signal.
 3. The radioapparatus as claimed in claim 2, further comprising checking means forchecking whether said radio signal includes information indicating asearch request for determining the position information of said radioapparatus.
 4. The radio apparatus as claimed in claim 2, furthercomprising storing means for storing said message.
 5. The radioapparatus as claimed in claim 2, wherein said setting means sets aresponse hold state and said sending means sends said message even ifsaid radio apparatus is capable of determining its position information.6. The radio apparatus as claimed in claim 1, further comprising:positioning means for determining its position information; and sendingmeans for sending the result of said positioning means to a sender ofsaid radio signal.
 7. The radio apparatus as claimed in claim 2, whereinsaid message indicates that said radio apparatus is incapable ofdetermining its position information.
 8. The radio apparatus as claimedin claim 3, wherein said message indicates that said radio apparatusrejects said request to determine its position information.
 9. The radioapparatus as claimed in claim 2, wherein said message is the latestpositioning data of a plurality of radio apparatus positioning data. 10.The radio apparatus as claimed in claim 2, wherein said message is theposition information of a base station located closest to said radioapparatus.
 11. The radio apparatus as claimed in claim 1, wherein saidradio apparatus is a portable telephone.
 12. The radio apparatus asclaimed in claim 4, wherein said radio apparatus receives radio signalsfrom a plurality of senders, and said storing means stores a message foreach one of the plurality of senders.
 13. The radio apparatus as claimedin claim 12, wherein at least one message stored in said storing meansis different from another message stored in said storing means.
 14. Aradio apparatus comprising: a receiver that receives a radio signal; apositioning mechanism that judges whether said apparatus is capable ofdetermining its position information; and a controller that sets aresponse hold state when said apparatus is incapable of determining itsposition information.
 15. The radio apparatus as claimed in claim 14,further comprising a transmitter that sends a message to a sender ofsaid radio signal.
 16. The radio apparatus as claimed in claim 15,further comprising a receiver controller that checks whether said radiosignal includes information indicating a search request for determiningthe position information of said radio apparatus.
 17. The radioapparatus as claimed in claim 15, further comprising a memory thatstores said message.
 18. The radio apparatus as claimed in claim 15,wherein said controller sets a response hold state and said transmittersends said message even if said radio apparatus is capable ofdetermining its position information.
 19. The radio apparatus as claimedin claim 14, further comprising: a positioning mechanism that determinesthe position information; and a transmitter that sends the result ofsaid positioning mechanism to a sender of said radio signal.
 20. Theradio apparatus as claimed in claim 15, wherein said message indicatesthat said apparatus is incapable of determining its positioninformation.
 21. The radio apparatus as claimed in claim 16, whereinsaid message indicates that said apparatus rejects said request todetermine its position information.
 22. The radio apparatus as claimedin claim 15, wherein said message is the latest positioning data of aplurality of radio apparatus positioning data.
 23. The radio apparatusas claimed in claim 15, wherein said message is the position informationof a base station located closest to said radio apparatus.
 24. The radioapparatus as claimed in claim 14, wherein said radio apparatus is aportable telephone.
 25. The radio apparatus as claimed in claim 17,wherein said radio apparatus receives radio signals from a plurality ofsenders, and said storing means stores a message for each one of theplurality of senders.
 26. The radio apparatus as claimed in claim 25,wherein at least one message stored in said storing means is differentfrom another message stored in said storing means.
 27. A position searchsystem including a first radio apparatus and a second apparatus, whereinsaid first radio apparatus comprises: receiving means for receiving aradio signal from said second radio apparatus; judging means for judgingwhether said first radio apparatus is capable of determining itsposition information; and setting means for setting a response holdstate when said first radio apparatus is incapable of determining itsposition information.
 28. The position search system as claimed in claim27, wherein said first radio apparatus further comprises sending meansfor sending a message to said second radio apparatus.
 29. The positionsearch system as claimed in claim 28, wherein said first radio apparatusfurther comprises checking means for checking whether said radio signalincludes information indicating a search request for determining theposition information of said first radio apparatus.
 30. The positionsearch system as claimed in claim 28, wherein said first radio apparatusfurther comprises storing means for storing said message previouslydetermined on the basis of said second radio apparatus.
 31. The positionsearch system as claimed in claim 28, wherein said first radio apparatussets a response hold state and sends said message to said second radioapparatus even if said first radio apparatus is capable of determiningits position information.
 32. The position search system as claimed inclaim 27, wherein said first radio apparatus further comprising:positioning means for determining its position information; and sendingmeans for sending the result of said positioning means to said secondradio apparatus.
 33. The position search system as claimed in claim 28,wherein said message indicates that said first radio apparatus isincapable of determining its position information.
 34. The positionsearch system as claimed in claim 29, wherein said message indicatesthat said first radio apparatus rejects said request to determine itsposition information.
 35. The position search system as claimed in claim28, wherein said message is the latest positioning data of a pluralityof radio apparatus positioning data.
 36. The position search system asclaimed in claim 28, wherein said message is the position information ofa base station located closest to said first radio apparatus.
 37. Theposition search system as claimed in claim 27, at least one of saidfirst radio apparatus and said second radio apparatus are portabletelephones.
 38. The radio apparatus as claimed in claim 30, wherein saidradio apparatus receives radio signals from a plurality of senders, andsaid storing means stores a message for each one of the plurality ofsenders.
 39. The radio apparatus as claimed in claim 38, wherein atleast one message stored in said storing means is different from anothermessage stored in said storing means.
 40. A position search method forsearching a position of a radio apparatus, said method comprises:receiving a radio signal; judging whether said radio apparatus iscapable of determining its position information; and moving to aresponse hold state when said radio apparatus is incapable ofdetermining its position information.
 41. The position search method asclaimed in claim 40, wherein said method further comprises sending amessage to a sender of said radio signal.
 42. The position search methodas claimed in claim 41, wherein said method further comprises checkingwhether said radio signal includes information indicating a searchrequest for determining the position information of said radioapparatus.
 43. The position search method as claimed in claim 41,wherein said method further comprises storing said message.
 44. Theposition search method as claimed in claim 40, wherein said methodfurther comprises: moving to a response hold state when said radioapparatus is capable of determining its position information; andsending a message to a sender of said radio signal.
 45. The positionsearch method as claimed in claim 40, wherein said method furthercomprises: determining its position information of said radio apparatus;and sending the positioning result to a sender of said radio signal. 46.The position search method as claimed in claim 40, wherein said radioapparatus is a portable telephone.
 47. The radio apparatus as claimed inclaim 43, wherein said radio apparatus receives radio signals from aplurality of senders, and said storing means stores a message for eachone of the plurality of senders.
 48. The radio apparatus as claimed inclaim 47, wherein at least one message stored in said storing means isdifferent from another message stored in said storing means.